But for an occasional drain line I've almost never done anything but brazing so I'm looking for advice on unsoldering and replacing a 15 ton Sporlan valve may have to change out.
About an inch and a half past the soft soldered outlet where I'd be making the repair and right at or into the case wall is the distributer head which is also soft soldered -that I do not want to get in to.
I'm concerned about possible problems getting a good connection over the old solder (let alone protecting the second joint). And also advice about flux, and keeping that out of the system?

..Seems like this may be a heck of a place to try to ramp up low temp torch skills